All categories

2 years ago

In the late 1 800s , experiments using cathode ray tubes led to the discovery of the

Chemistry

1 answer:

Mice21 [21]2 years ago

7 0

In the late 1800's, experiments using cathode ray tubes led to the discovery of the;

Electron(s)

It was founded that many different metals release cathode rays, and that cathode rays were made of electrons, very small negatively charged particles.

You might be interested in

200 g of solid sodium hydroxide (NaOH) are dissolved in 750 mL of water. What is the concentration of this solution?

Anastaziya [24]

Answer:

6.67 M

Explanation:

Molarity = $\frac{mol}{L}$

Convert 200g NaOH to moles. Convert 750 mL to L.

200 g NaOH x (1 mol/39.998 g) = 5.00025... mol NaOH

750 mL x (1 L/1000 mL) = 0.750 L

Substitute values into the equation.

Molarity = $\frac{5.00025}{0.750}$

Molarity = 6.667... M

Molarity = 6.67 M

8 0

2 years ago

Read the information about the three atoms given in the table. Which of them are isotopes of each other

lara [203]

I think that the answer could be A. X and Y

5 0

3 years ago

Please someone help me out thank you I’ll give brainlist :))

Tom [10]

Answer:

Ionization energy increases going left to right across a period and increases from bottom to top in a group

Electron affinity increases when going up a group

If we are excluding noble gases (aka group 8/18), Chlorine is the element that has the greatest electron affinity. This is because Fluorine's 2p orbital is limited and packed which doesn't quite allow sharing of the orbital with extra electrons easily, while Chlorine has a 3p orbital allowing more space for electrons, where the orbital electrons would be inclined to do so.

Helium is the element with the greatest ionization energy since it's at the top and energy (from Oganesson to Helium) increases when going across a period (from Hydrogen to Helium).

4 0

2 years ago

Iron and vanadium both have the BCC crystal structure and V forms a substitutional solid solution in Fe for concentrations up to

Bess [88]

Answer:

Explanation:

To find the concentration; let's first compute the average density and the average atomic weight.

For the average density $\rho_{avg}$ ; we have:

$\rho_{avg} = \dfrac{100}{ \dfrac{C_{Fe} }{\rho_{Fe}} + \dfrac{C_v}{\rho_v} }$

The average atomic weight is:

$A_{avg} = \dfrac{100}{ \dfrac{C_{Fe} }{A_{Fe}} + \dfrac{C_v}{A_v} }$

So; in terms of vanadium, the Concentration of iron is:

$C_{Fe} = 100 - C_v$

From a unit cell volume $V_c$

$V_c = \dfrac{n A_{avc}}{\rho_{avc} N_A}$

where;

$N_A$ = number of Avogadro constant.

SO; replacing $V_c$ with $a^3$ ; $\rho_{avg}$ with $\dfrac{100}{ \dfrac{C_{Fe} }{\rho_{Fe}} + \dfrac{C_v}{\rho_v} }$ ; $A_{avg}$ with $\dfrac{100}{ \dfrac{C_{Fe} }{A_{Fe}} + \dfrac{C_v}{A_v} }$ and

$C_{Fe}$ with $100-C_v$

Then:

$a^3 = \dfrac { n \Big (\dfrac{100}{[(100-C_v)/A_{Fe} ] + [C_v/A_v]} \Big) } {N_A\Big (\dfrac{100}{[(100-C_v)/\rho_{Fe} ] + [C_v/\rho_v]} \Big) }$

$a^3 = \dfrac { n \Big (\dfrac{100 \times A_{Fe} \times A_v}{[(100-C_v)A_{v} ] + [C_v/A_Fe]} \Big) } {N_A \Big (\dfrac{100 \times \rho_{Fe} \times \rho_v }{[(100-C_v)/\rho_{v} ] + [C_v \rho_{Fe}]} \Big) }$

$a^3 = \dfrac { n \Big (\dfrac{100 \times A_{Fe} \times A_v}{[(100A_{v}-C_vA_{v}) ] + [C_vA_Fe]} \Big) } {N_A \Big (\dfrac{100 \times \rho_{Fe} \times \rho_v }{[(100\rho_{v} - C_v \rho_{v}) ] + [C_v \rho_{Fe}]} \Big) }$

Replacing the values; we have:

$(0.289 \times 10^{-7} \ cm)^3 = \dfrac{2 \ atoms/unit \ cell}{6.023 \times 10^{23}} \dfrac{ \dfrac{100 (50.94 \g/mol) (55.84(g/mol)} { 100(50.94 \ g/mol) - C_v(50.94 \ g/mol) + C_v (55.84 \ g/mol) } }{ \dfrac{100 (7.84 \ g/cm^3) (6.0 \ g/cm^3 } { 100(6.0 \ g/cm^3) - C_v(6.0 \ g/cm^3) + C_v (7.84 \ g/cm^3) } }$

$2.41 \times 10^{-23} = \dfrac{2}{6.023 \times 10^{23} } \dfrac{ \dfrac{100 *50*55.84}{100*50.94 -50.94 C_v +55.84 C_v} }{\dfrac{100 * 7.84 *6}{600-6C_v +7.84 C_v} }$

$2.41 \times 10^{-23} (\dfrac{4704}{600+1.84 C_v})=3.2 \times 10^{-24} ( \dfrac{284448.96}{5094 +4.9 C_v})$

$\mathbf{C_v = 9.1 \ wt\%}$

4 0

2 years ago

What of these should Hailey include in her list?

Natalka [10]

Answer:

Hailey should add, they are inexpensive to produce.

Explanation:

Reason being why they are inexpensive to produce, is due to them being chemical based and easy to product in the factory setting. Which makes them extremely cheap to make.

Reason being why the others are wrong, synthetic polymers are not biodegradable as they are made in a factory with oils. Synthetic polymers are not flexible due to them being used for harder products. Synthetic polymers are not recycled cheaply as they are made with chemicals which makes it very hard to recycle.

5 0

2 years ago